A database is divided into logical storage units called tablespaces, which
group related logical structures together. Each Tablespace in turn consists of
one are more datafiles.

In relational database system all the information is stored in form
of tables. A table consists of rows and columns

All the tables and other objects in Oracle are stored in tablespace logically, but
physically they are stored in the datafiles associated with the tablespace.

Every Oracle database has a set of two or more redo log files. The set of
redo log files for a database is collectively known as the database's redo log.
A redo log is made up of redo entries (also called redo records).

The primary function of the redo log is to record all changes made to data.
If a failure prevents modified data from being permanently written to the
datafiles, the changes can be obtained from the redo log so work is never lost.

Every Oracle database has a control file. A control file contains the
database name and locations of all datafiles and redo log files.

Every Oracle database also has a Parameter File. Parameter file contains the
name of the Database, Memory Settings and Location of Control file.